Convert to CoffeeScript

This starts the conversion of jQTouch to CoffeeScript. Trolls can butt out: I've preferred CoffeeScript for a long time, and this will help make updates/fixes to the library faster for me.

This patch is not yet finished, but I wanted to PR now so Thomas can start testing and reviewing. During the conversion, I also spotted several places for optimization, fixed a few bugs, and started tweaking the default theme just a bit.